Hexagonal boron nitride nanosheets as metal-free electrochemical catalysts for oxygen reduction reactions |
| |
Affiliation: | 1. Fujian Provincial Key Laboratory of Functional Materials and Applications, School of Materials Science and Engineering, Xiamen University of Technology, Xiamen, 361024, China;2. Department of Chemical Engineering and Materials Science, Yuan Ze University, Taoyuan, 32003, Taiwan;3. Department of Mechanical, Aerospace, and Biomedical Engineering, University of Tennessee, Knoxville, TN, 37996, United States;4. Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02142, United States |
| |
Abstract: | A high-performance ball milling technique was developed for synthesizing hexagonal boron nitride (h-BN) carbon paper (CP) electrodes as metal-free catalyst for the oxygen reduction reaction (ORR) and hydrogen storage (electrochemically) in acidic media. The h-BN nanosheets were functionalized with glycine to enhance the number of active sites and to boost the catalytic activity. The ball-milled h-BN catalytic electrodes demonstrated ultra-high catalytic activity toward electrochemical hydrogen adsorption/desorption (~3.5 times higher than pristine electrodes) as well as ORR in acidic electrolytes. Furthermore, in-situ durability analysis of the h-BN electrodes was performed via conducting a long-duration cycling experiment (>200 cycles). A mechanistic reaction pathway (sequential) including chemisorption and charge transfer reactions (four-electron and two-electron pathways) was also proposed for the ORR. Considering superior catalytic activity of as-prepared h-BN/CP electrodes, this class of metal-free nanostructured materials can be employed as inexpensive catalysts for the electrochemical H-storage and ORR within various energy storage/conversion devices (e.g., batteries, electrolyzers, and fuel cells). |
| |
Keywords: | Hexagonal boron nitride Electrochemical catalysts Oxygen reduction reaction Catalytic activity Two-dimensional sheets |
本文献已被 ScienceDirect 等数据库收录! |
|